Colposcopy and Treatment of Cervical Intraepithelial Neoplasia - RHO

Chapter 4
Table 4.1: Indications for colposcopy
Suspicious-looking cervix
Invasive carcinoma on cytology
CIN 2 or CIN 3 on cytology
Persisting (for more than 12-18 months) low-grade (CIN 1) abnormalities on cytology
CIN 1 on cytology
Persistently unsatisfactory quality on cytology
Infection with oncogenic human papillomaviruses (HPV)
Acetopositivity on visual inspection with acetic acid (VIA)
Acetopositivity on visual inspection with acetic acid using magnification (VIAM)
Positive on visual inspection with Lugol’s iodine (VILI)
high-grade lesion that would be found at colposcopy;
perhaps 15% for those with atypia and 20% with CIN 1
on cytology may harbour higher-grade lesions (Shafi et
al., 1997). It is advisable that women with any grade of
CIN on cytology be referred for colposcopy in
developing countries, in view of the possibility of
reporting misclassification associated with cytology and
poor compliance with follow-up.
Abnormal cytology results are tend to be quite
worrying for a woman, as is a visit for a colposcopic
examination. A few clinical caveats are worth
mentioning. If the clinician observes characteristics of
a cervix that looks suspicious, no matter what the
cytology shows, it is advisable to refer the woman for
colposcopic examination. Likewise, observation of an
area of leukoplakia (hyperkeratosis) on the cervix
should prompt a colposcopic examination, since the
leukoplakia can not only obscure a lesion, but also
preclude adequate cytological sampling of the area. It
is still uncertain whether women with external
anogenital warts are at increased risk of CIN; although
it is clear that they should have routine cytology
smears, it is not certain whether they would benefit
from colposcopic examination (Howard et al., 2001).
The potential roles of 3-5% acetic acid application
and subsequent visual inspection of the cervix with
magnification (VIAM) or without (VIA) and of visual
inspection with Lugol’s iodine (VILI) are still under
study as screening techniques (University of Zimbabwe,
JHPIEGO study, 1998; Denny et al., 2000; Belinson et
al., 2001; Sankaranarayanan et al., 2001). Women who
are positive for these tests may be referred for
colposcopy to rule out underlying high-grade CIN and
invasive cancer.
Instrumentation
Hinselmann (1925) first described the basic colposcopic
equipment and its use, establishing the foundation for
the practice of colposcopy. A colposcope is a low-power,
stereoscopic, binocular, field microscope with a
powerful variable-intensity light source that illuminates
the area being examined (Figure 4.1).
The head of the colposcope, also called the ‘optics
carrier’, contains the objective lens (at the end of the
head positioned nearest to the woman being
examined), two ocular lenses or eyepieces (used by the
colposcopist to view the cervix), a light source, green
and/or blue filters to be interposed between the light
source and the objective lens, a knob to introduce the
filter, a knob to change the magnification of the
objective lens, if the colposcope has multiple
magnification facility and a fine focusing handle. The
filter is used to remove red light, to facilitate the
visualization of blood vessels by making them appear
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